When one wishes to use a regular or conventional toothbrush outside of home, it must be carried along with a toothpaste tube. The conventional tube is deformable, so that, when one takes the lid off and presses on the opposite end of the tube, the paste comes out to later be spread on the bristles.
The inconveniences of such a procedure outside of home are evident: it requires more space to carry the utensils; if taken inside a pocket, different pressures may produce an outflow of toothpaste, staining the garment or, even worse, the lid may be lost because of its size; it requires more time, more specific places and both hands free for dosing.
On the other hand, it's very well known that disposable objets are increasingly preferred, and it is desirable to be able to dispose of the toothbrush once the toothpaste is finished, giving the object a lifespan.
This problem has given rise to a large number of innovations: existing patents on the subject are uncountable. In terms of establishing the state of the art, and with no intention of being limiting, three contemporary different precedents will be mentioned here.
The United States patent U.S. Pat. No. 6,390,103 B1, dated May 21st, 2003, presents a set combining a toothbrush, toothpaste container, and a dental floss dispenser in a single unit with a main body, a head, a refill access part, and a base. The main body has a chamber designed to contain a certain amount of toothpaste. The head part holds the bristles to clean the user's teeth. Among the bristles there is a series of minute orifices selectively communicating with the toothpaste chamber. This product allows the refill of toothpaste by means of screwing a standard toothpaste tube onto the unit.
The United States patent U.S. Pat. No. 6,481,910 B1 is another invention of a toothbrush with a cylindrical handle which receives and stores toothpaste. By means of a twist on its end, the toothpaste is forced to move along a tubular canal toward the bristles. This end is detachable to allow the refill.
The United States patent U.S. Pat. No. 6,533,485 B1 is also a toothbrush invention with a long, hollow handle in which a certain amount of toothpaste has been stored and with a pressuring piston like device running along a longitudinal slot. Attached to this device there is a gauge or meter designed to indicate how much toothpaste is left in the chamber. The bristle head also has minute orifices in permanent communication with the cavity in the hollow handle.
As one can see, from the preceding art the devices all include a toothpaste deposit within the toothbrush handle, a tube or canal connecting the toothpaste chamber with the bristle head, minute orifices among the bristles and a device that ejects the toothpaste onto the bristles. However, all these devices have defective parts or concepts which the present invention solves.
Referring to the first example the brush is rechargeable, which means that the bristles, as well as the mounting system and materials, must be of good quality, since the brush is supposed to last several refills. This definitely increases its cost.
An identical problem is present in the second example, with the addition of not being able to handle the whole dosing process with just one hand.
In the third example, the toothbrush is disposable, but the quantity of toothpaste provided is small because its handle is thin. Thus, the product cost is low but its life span is short requiring the user to buy the product within shorter periods of time. This makes the product expensive from the user's point view.
In all of those known devices, toothpaste dosing must be carefully carried out by the user, since the process required to meter out the paste does not include a dosing trigger. This is not as easy to do as it seems, it requires concentration. The last end of paste chamber, by being exposed to the outside environment, may have dried out or contain low humidity toothpaste, especially if the toothbrush hasn't been used for several days. In this case the user may apply too much pressure onto the tube to force the dry paste to come out. Once the dry paste is overcome, however, the fluid paste, by being under pressure, may strongly be ejected from the chamber generating an overdose or, even worse, a spill.
Also, and finally, the toothbrushes here described as previous art, have the toothpaste container always exposed to the air through the minute orifices, generating the slow drying out of the paste.